Neutron inelastic scattering of the methyl torsional mode in hydrogenated and deuterated 4-methylpyridine crystals at 5 K

✍ Scribed by N. Le Calvé; D. Cavagnat; F. Fillaux

• Publisher: Elsevier Science
• Year: 1988
• Tongue: English
• Weight: 294 KB
• Volume: 146
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(88)87499-2

✦ Synopsis

Inelastic neutron scattering from the 4-methylpyridine crystal (C6H7N) and its perdeuterated analogue (C6D7N) were recorded at 5 K in the O-9.5 cm-' range. The main intensities appear at 4.16 and 0.8 cm-' for the hydrogenated and deuterated compounds, respectively. They are ascribed to the methyl torsional mode and the isotopic ratio (4.16/0.8 z 5) indicates a tunnel splitting consistent with a periodic potential. In addition, there is a weak band at 3.82 cm-' for C6H7N which is ascribed to the r(CH>) mode, although the analogous band could not be identified in the deuterated derivative. The methyl torsion dynamics is thus likely to be more complicated than suggested by a simple periodic potential.